Why was my own writing flagged as AI?

Detectors measure predictability, not authorship. Short, formal, or highly polished writing, and writing by non-native English speakers, is more predictable and gets flagged more often, even when it's entirely original. Grammar tools that smooth your prose can push it further that way.

If you're accused, keep your drafts and version history as evidence of your process, ask for a human review, and point to the detector vendor's own guidance that a score is not proof. Varying your sentence rhythm and adding specifics usually lowers the estimate.